JavaRush/Courses/Kotlin Course

Kotlin Course

Want the language of the future? Kotlin — Google's official choice for Android, used by Netflix, Uber, Trello. 62 levels of practice: coroutines, null-safety, functional programming. 1000+ tasks — a record among all Kotlin courses! Instant verification with AI validator. Become a skilled Kotlin developer!
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Detailed training program
  • Commands and the first program in Kotlin
  • Integers, strings, and user input: readln()
  • Conditional operators and logic
  • Loops for flow control
  • IDE setup and Kotlin project configuration
  • Floating-point numbers and their peculiarities
  • Arrays in Kotlin + ranges and progressions
  • Functions and their structure
  • Advanced string operations
  • Pair/Triple and local functions
  • Null-safety and safe null handling
  • Exception handling: try/catch/finally
  • when: branching, validation, commands
  • Input/validation functions: designing a mini utility API
  • Mini-project #1: "Guess the Number" game
  • vararg and spread: convenient functions
  • Project / Packages / Imports
  • Introduction to Git: why version control matters
  • GitHub: commit / branch / merge / PR, conflicts
  • Collections List/Set/Map, mutable/immutable, generics: starting the end-to-end project
  • Iterating collections: Iterable, withIndex, entries, safe removals
  • Lambdas and callable references in collection tasks
  • Collection operations I: map/filter/find/any/all/count/mapNotNull
  • Collection operations II: sorting, compareBy, top-N via take(n), == vs ===
  • Groupings and frequencies: groupBy, groupingBy().eachCount()
  • Aggregations and pipeline performance: fold/reduce, Sequence
  • Workshop: reports and transformation pipelines
  • Strings in depth + Regex + takeIf/takeUnless
  • Scope functions and mini-project #2: Text Analyzer
  • Java interoperability: platform types, SAM, Java API
  • Classes and objects: properties, methods
  • Constructors and init: primary/secondary, require/check
  • Properties: encapsulation, lateinit/lazy
  • data class and value class
  • enum and sealed class, is/as/as?, exhaustive when
  • Inheritance and polymorphism
  • Generics in depth: variance (out/in), projections, inline/reified
  • Interfaces, SAM + object/companion object
  • Extensions and operators
  • Architecture and refactoring: end-to-end project
  • Exceptions: Result, runCatching, error design
  • Null-safety: null-free design, smart-cast limitations
  • Files: reading/writing, use, paths
  • Files: binary, buffers, chunk copying, ZIP
  • Encodings and BOM
  • Reliable I/O: IOException, atomic write, backup
  • Mini-project #3: File Organizer
  • JSON + kotlinx.serialization
  • Serialization: enum/sealed, annotations
  • JsonElement, validation, JSON vs XML
  • XML workshop: DOM/XPath
  • Dates and time: kotlinx.datetime, time zones, parsing/formatting
  • Coroutines: suspend, runBlocking, launch/async, Dispatchers
  • Structured concurrency: scope/job, cancellation, exceptions, withContext
  • Channel and Flow
  • Synchronization: Mutex, Atomic*, actor/confinement
  • Asynchronous I/O and cancellation
  • Events/Observer and integration with Flow
  • HTTP + Ktor Client + JSON
  • Databases: JDBC + Exposed + transactions
  • Logging and observability
  • Reflection + KSP + Kotlin 2.x + JVM memory
330+
Lectures
1000+
Tasks
61
Tests
Also:
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  • WebIDE
  • Gamification
  • Motivational lectures